Skip to content

    Brain & Nervous System Health Center

    Font Size

    Amateur Boxers at Risk of Brain Injury

    Even Mild Blows Can Cause Brain Damage, Study Shows
    WebMD Health News
    Reviewed by Louise Chang, MD

    May 2, 2007 (Boston) -- A new study gives added scientific meaning to the term punch drunk.

    Researchers report that even the relatively mild blows to the head incurred by amateur boxers appear to cause brain damage.

    The researchers analyzed the cerebrospinal fluid of 14 amateur boxers for protein markers of brain injury. Levels of one particular marker for brain damage, known as neurofilament light (NFL) protein, were four times higher in boxers within 10 days of the fight than in healthy nonboxers.

    In the study, the boxers were tested both after a fight and then again three months after their last match. NFL levels were still elevated three months later.

    Researcher Max Hietala, MD, PhD, of Sahlgrenska University Hospital in Goteborg, Sweden, tells WebMD that the Swedish boxers studied were wearing helmets that were much better padded than those generally used in U.S. amateur fights.

    “Regardless of the gear, if they got hit more than 15 times, it was like having a mini-stroke,” he says.

    NFL levels were up to eight times higher in amateur boxers who received more than 15 high-impact hits to the head after a match than after the three-month rest.

    “Given that amateur fights are much shorter and generally involve milder head blows than pro fights, you can just imagine what’s happening to professional boxers,” James Kelly, MD, visiting professor of neurosurgery at the University of Colorado in Denver, tells WebMD. Kelly was not involved with the work.

    The study was presented at the American Academy of Neurology’s annual meeting.

    Repeated Hits Cause Brain Cells to Die

    Hietala says a well-thrown punch carries more than a half-ton of force.

    He says that the hits cause brain cells to die. Then they leak proteins into the cerebrospinal fluid.

    “If you get a concussion, you’ll also have elevated NFL levels, but there’s nothing you can do,” Hietala says. “With boxing, you can.”

    “We’ve seen some studies [on this topic before], but this is much more scientifically detailed, with finer testing,” Kelly says. “This is truly worrisome.”

    Not all the news is distressing: The researchers found that no evidence of increased levels of NFL or other markers of brain injury in medical students who volunteered to repeatedly hit a soccer ball with their heads.

    “Our conclusion is that hitting a soccer ball with your head is not dangerous,” Hietala says.

    Today on WebMD

    nerve damage
    Learn how this disease affects the nervous system.
    senior woman with lost expression
    Know the early warning signs.
    woman in art gallery
    Tips to stay smart, sharp, and focused.
    medical marijuana plant
    What is it used for?
    woman embracing dog
    boy hits soccer ball with head
    red and white swirl
    marijuana plant
    brain illustration stroke
    nerve damage
    Alzheimers Overview
    Graphic of number filled head and dna double helix